System and method for improving dynamic performance of a circuit

Abstract

A system and method for improving the dynamic performance in an analog-to-digital converter (ADC) by randomizing the differential mismatch. The differential mismatch in an input analog signal is randomized by flipping the input signal and output signal randomly.

1. A method for improving the dynamic performance of a circuit, the method comprising the steps of:
 randomly multiplying an input signal of the circuit with a pseudo random bit sequence in an input stage to produce a modified input signal; 
 processing the modified input signal in the circuit to generate a modified output signal; and 
 multiplying the modified output signal with the pseudo random bit sequence used at the input stage to produce a final output signal, whereby even harmonics in the final output signal are randomized. 
 
     
     
       2. The method according to  claim 1 , wherein the pseudo random bit sequence comprises a random sequence of positive and negative values. 
     
     
       3. The method according to  claim 2 , wherein the positive values are +1 and the negative values are −1. 
     
     
       4. The method according to  claim 1 , wherein the circuit is an analog-to-digital convener (ADC) circuit. 
     
     
       5. The method according to  claim 1 , wherein the circuit is a switched capacitor circuit. 
     
     
       6. The method of  claim 1  further comprising: removing noise due to offset in the circuit. 
     
     
       7. A system for improving the dynamic performance of a circuit, the system comprising:
 a pseudo-random bit sequence generator for generating a pseudo random bit sequence; 
 a first multiplier for multiplying an input analog signal with said pseudo random bit sequence to provide a modified analog input signal; 
 a circuit core for receiving said modified analog input signal as input and for converting said modified analog input signal to a modified digital output signal; and 
 a second multiplier for multiplying said modified digital output signal with said pseudo random bit sequence to generate a final output signal.